Tandem conveyor



Sept. 10, 1957 G. F. H. VON STROH ET Ai. 2805760 TANDEM CONVEYOR Filed April l. 1955 INVENTORS p 1957 ca. F. H. VON STROH ET Ai. 2805,760

' TANDEM CONVEYOR I 4 Sheets-Sheet 2 Filed April l. 1955 Sept. 10, 1957 G. F. H. VON STROH ET Ai. 280576 TANDEM CONVEYOR 4 Sheets-Sheet 3 Filed April l. 1955 INVENTORS A'ITORNEY Spt 1957 G. F. H. VON STROH ET Ai. 2,805,760

TANDEM CONVEYOR 4 Shee'ts-Shee't 4 :iled April l. 1955 Unitcd State:s Patent O TANDEM CONVEYOR Gerald F. H. von Stroh and Howard J. Thomas, Huntington, W. Va. assignors to Bituminous Coal Research, Inc., Washington, D. C., a corporation of Delaware Applicatioza April 1, 1955, Serial No. 498,534

12 Claims. (C1. 19892) This invention relates to a tandem system for conveying materials and, more particularly, to the individual conveying units employed in such a system which are designed to be readily interlocked togther and driven by a common power source. The invention is particularly suitable for use in the coal mining industry where flexibility, portability and ease of interconncction of several units in driving relationship a1e factors of the utmost importance.

Ordinary trough flight conveyor systems are, of course, well known. However, the common type of endless belt conveyor troughs exhibit many inherent disadvantages. By and large, each trough of such a system is separatcly driven 01, if commonly driven, by means most cumbersome to use and extrernely inefiicient so far as porbability, connection and interchangeability be concerned.

Prior devices are also inflexible and cumbersome to use in the sense that, if driven from a common ower source, the manner of transmission of power to the, required number of troughs is such that the individual units can not be displacedcither laterally or vertically with respect to each other to any substantial degree without cousiderable efiort, if a1; all. Also, the manner of interconnection and disassembly, where difficult and tirneconsuming, has detracted from the practical utility of such deviccs.

Our invention is unique in providing a common drive rneang which permits a simplified and eflortless interconnection of a series of fiight conveyors with no restriction as to the number which may be so employed except the limitations indicated by the output of the power supply.

Accordingly, it is an objective of this invention to provido a flight conveyor unit of the trough type which is fitted witha transmission mechanism of a nature that will readily permit attachment and detachment of a series of such units.

It is a further object of this invcntion to provide means for employing, in most instances, only one common ower source, thereby substantially eliminating a multitude of fluid or electric motors for each individual unit used in the conveyor system.

An additional object of the invention is the provision of a connecting type of interlock mechanism by which the drive means and accompanying transmission incorporated therein can be quickly and easily connected or unconnected With rcspect to adjacent units.

A further object of the invention is to provide a system. of conveying wherein such groups of conveyor units. may be easily transported from place to place whether or not they are interconnected in large or small numbers.

Another object of the invention is the provision of such conveyor units which not only can be rapidly interlocked together, but also that represent, at the same time, a hi gh degree of flexibility; here, reference is made to the fact that the interlock and accompanying transmission in each unit are so arranged and constructed that they d 2,8@5,750 Patented Sept. 10, 1957 not interfere with movemeint of the individual unlts with respect to ech other either laterally o1 vertically to a substantial degree. It is evident that where systems such as these are employed in coal mines, it must be possxble to angularly incline each unit with respect to adjacent units, either vertically or laterally, so that the entire series can be positioned to follow the contour of the room or series cf rooms without undue hindrance.

These advantages and objects of the invention will more fully appcar f1'om the following description made in counection with the accompanying drawings. Referring to the latter, like reference characters refer to similar parts throughout the several views. In these views:

Figure 1 is an eleva'tion, largely diagrammatic view of the invention, illustrating its use in conjunction wlth a trammer, the latter being of a tractor type and having a common power source which is interconnected with the last in line cf aseries of conveyor units;

Figure 2 is a view similar to Figure 1 but illustrating further the employrnent of a booster motor in one of a series of conveyor units;

Figure 3 is a plan view, largely diagramrnatic, indicating the side angles of inclination with respect to the lateral, as regards individual conveyor units, which may be obtained through the use of our invention;

Figure 4 is a detailed view in cross section, taken on the line 44 of Figure 5, illustrating the transmis sion assembly interconnecting the inby end of one unit With the outby end of the adjacent unit, and further showiug the manner of interlock of two adjacent conveyors;

Figure 5 is a detailed sectional view;taken on the line 5-5 of Figure 4; 4

Figure 6 is a plan view, partially in section, of the gear arrangement comprising part of the transmission assembly;

Figure 7 is a detailed view, partially on the line 7-7 of Figure 4;

Figure 8 is an elevation view, partially in section, showing the manner in which a booster motor may be employed in conjunction with any one of several c0nveyor units; and

Figure 9 is a'detailed view of the slide assembly used in the interlock mechanism.

Referring more particularly to the drawings, it is seen that the system includes not on1y the individual couveyor units generally indicated at A, but also an adjustable dischargeconveyor B, here shown as surmounting the trammerand employed to discharge the conveyed materials to adjacent cars 01' other conveying means. All units, as stated, may receive their main power supply .through ower means placed upon the tramme'r, generally indicated at C. As indicated in Figure 1, the inain drive, preferably a hydraulic motor D, is located at the outby end of the last in line cf a serics of conveyor units. Fluid pressure for operation of motor D is obtained from pumps P on the trammer. Such motor can be interconnected with the last of these units through a suitable transmission in any conventional manncr, the particulaf means for doing so comprising no part of the instant in- Vent1on.

Also, referring:to this sarne figure (Figure l), it is to be understood that, in referring to forward and rear units, or the forward end 0r rear end of an individual unit, forward would desigriate the unit on the right of this figure; the'forward end of each unit being that end receiving the material from the sourceof supply; and the rear, that end nearest the trammer. The

in section, taken arrows in Figurc 1 thus indicate direction of traVel of thc conveyed material. 1

In the preferred embodirnent of our invention, as herein described, the scve'ral troughs include sides 10, tho

channels 118, somewhat smaller jn height than channels 20 and directly affixecl to the latter by welding the lowef flanges of ehannels 118 inthe relative positions indicated in Figure 4.

Surmou.uting these two side channels 118 is a relatively strong supporting plate 120. The transrnission unit, as Will be obvious, is thus supported, and aflixed to, this plate. Referring more particularly to the two separate transmission casings, it is seen that housing 116 is forrnkad of two separate elements 122 and 124 joined.together by a series of bolts 129 secured to the flanged rims 127 of each of the elements 122, 124. These upper and lower plates 122 and 124 terminate in a semicircular configration 121, formed on each side, as shown in Figure 6. Similarly, the relatively movable hou'sing 115 is also composed of two opposed plate members 126 and 128 secured in a like manner, through bolts 129 along the respective rims thereof, to each other. These two elements 126 and 128, forming housing 115, also terminate in two semicircular configurations 123 on each side of said elements. The curved portions 123 form the arc of a circle slightly larger than the cireular periphery formed by the elements 121. The integration of this structure should be apparent. The semicircular configurations 121 are aapted to slide within the larger circular configurations 1 3.

In order to keep the transmission gearing substantially free of contamination, we prefer to employ means for sealing the contacting surfaces of the two curved elements 121 and 123. This takes the form of flanges 133 affixed to the larger, outer. chrved portions 123, such flanges terminating in right angular extensions 132. Compressed in the groove formed by extensions 132 are located packing elements 134, the latter pressing against the inner circular configurations in sealing engagement in a well understood manner.

Although the two housings 115 and 116 are practically the Same in all other respects, theelements 122, 124 of housing 116, and forming the top and bottorn thereof respectiveiy, are parallel to each other and spaced the sarne distance apart. In thecase of housing 115, the two compleme-ntary top and bottorn plates, plates 126 and 128, are separated a somewhat greater distance apart at the portions thereof near the pivot point of this housing. The separation or distance between these parallel plates is of sufiicient amount to encase the plates of housing 116 therebetween. In this manner, housing 115 terminates in raised portions 126 and 128 which, as just described, are adapted t0 embrace the end portion of housing 116. Thus, so far as these two transrnission housings 115 and 116 are concerned, it is Seen that the structure of the casings thereof is such that housing 115 can rotate about its pivot point with respect to housing 116 at all times, even during operation of the transrnission assembly.

In the preferred embodiment of the invention, as herein described, power is transmitted from stub shaft 110 thr'ough a series of five gears of equal size. These gears, as seen in Figure 4, are designated by the numerals 140, 150, 160 and 170. T he gea'rs are rotated in a series of annuluses er circular ribs formed upon the inner sides of each of the casin-g elements 122, 124, 126 and 128. For emample, the hub of gear 130is embraced by annulus 131 in platte 122 and also annulus 132 in plate 124. Sinailarly, the annuluses 141 and 142 embrace the hub of gear 140; ribs, 151 and 152, the hub of gear 150; elements 161 and 162, the hub of gear .160; and curved mernbers 171 and l72, the hub of gear 170. In between each of the hubs of these respective gears and the respective annuluses embracing the same are located antifriction bearings 135 of usual design, here shown as ball bearing faces. It is thus app|arent that this series of elements is adapted to transfer whatever torque is delivered to gear 130 through the series to gear 170, and thatthis can be av ccomp lished although casing is positioned or angled a substantial distance laterally about its pivot point.

Power is supplied to the initial gear of this gear train through stub shaft 110. The latter terminates in an enlarged hub 175 and is keyed by key 176 to gear 130. Only the two end gears a.re keyed to drive shafts, the intermediate gears 140, and freely rotating Within their respective ball bearing races, retained, as described above, by their respective series of circular rib formations. In any event, the last of the series in gear train, gea1 170, is, like gear 175, keyed to an enlarged portion 172 of a stub shaft 173. The key is indicated at 174. The stub shaft 173 terminates in a squared end 200 adapted to engage a eorresponding opening in the shaft supporting one of the bevel gears to be referred to hereinafter.

I-Iousing 115 and the described gear elements coutained therein may rotate about the central gear 150, such rotation or angular inclination to housing 116 being in the plane of the horizontal. Actually shaft 180, abo'ut which gear 150 rotates, is the pivot point for such movement. The various plates forming the two ho1isings, such l3S plates 122, 124, 126 and 128, are all suitably apertured to receive shaft 180. The latter is reduced in diameter at its lower portion, as indicated at 183, and that Portion extends through the supporting plate 120. Bushings 182 and 105 are placed on each end of the shaft to embrace the upper housing plate 126 and the supporting plate 120, as shown in Figure 4. This entire structure, including housing 116 and the related gear train, is then further maintained in place by an appropriate nut 188. This is tightened to a degree sufficient to retain the structure in position Within desirable tolerances but insufiicient to bind the two housings in such degree to reduce ease cf movement of housing 115 with respect to oasing 116.

The pivot shaft also provides the support for a ball of a ball and socket interlocking mechanism. This ball 190, having a stem 192, is threaded at one end and adapted to be screwed into an appropriate aperture in the pivot shaft 180. When located at the desired position With respect to each other, the shaft 180 and ball are permanently maintained together by pin 196.

Referring to Figure 4, it Will be recalled that the outby end of the conveyor unit is here shown with shaft 86 supported in the two side channels 20. At one end, the shaft is journaled in an appropriate bearing 208 secured against a bushing 210 by bolts 212. The two channels 20 are spaced a predetermined distance apart by a plate 205 fastened to the lower flange 01 each of them.

At the opposite end of shaft 86, a plate 215 is secured in place across the web of the adjacent channel 20. Secured to this shaft plate 215 is an additional plate218, secured by the usual bolts 219 and having a spaced circular flange 225 which provides a channel between the plate 215 and the flange 225. The purpose of this construction is to secure the journal box 230, housing the bevel gears, to the conveyor frame in such manner that the conveyor unit can be raised or lowered vertically without interfering with the transrnission of power through the series of gears described above. T0 this end, it is seen that the journal box 230 has a thickened portion 235 upon its side near the conveyor frame; this thickened portion is provided with a circular flange 228, to fit into the corresponding circular groove formed by the spaced flange 225 already referred to. Also, the thickened ortion 225 is provided With a circular groove 233 to receive flange 225. The result is a double tongueand-groove sliding arrangement Which permits, as stated, the members 215 and 225, all secured to the conveyor assernbly, to rotate on the horizontal axis of shaft 86, with respect to the journal box 230.

The shaft 86 is, of course, provided with a bevel gear 245, journaled in the usual type of antifriction bearing 242, the latter being spaced by. a bushing 240 from the Wall 215, previously dest:ribed.

Sliaft 5-!i ada ns s 2 n 11 Well l@ JQQ 1 mann 2:-. i h h iS q id d w l an e r le .I LRQNQ 126. having. qu re P6 .n8 b. l tiogeceive the squared end 200 of the adjacent s'tiib s haft' Bevel gear 250 likewise is journaled in suitable anti friction rceways 251 retained in place by a plate 254 secured by bolts 256 to the mainhodyportion of the journal' box 230.

It should here be not ed that not -only does the foregoing structure per rnit vertieal tilting, either up or down, ofi the conveyor unit to a prac tically unlimited degree, laut also that lateral deflection can be obtained withont interfering with the drive asslexnbly whatsoever. No rf'njattet in what direction the unit is angularly inclined laterally, or in a horizontal plane, the two bevel gears 245 and 250: will mesh in the sarne' manner. Also, the drive assembly irrespective of lateral or vertical deflection of adjacent conveyor units, will operate Wllh the sarne degree of utility.- These functions can be more readily understood by reference to Figure 4 where it will be appr eciatedthat the rig'ht transmission housing 115 pivots al'aout pivot l80.within the suggested limitation of 35 ax;gularity thereto in a horizontal plane. Thus, when the superimposed conveyor unit is turned laterally, it will carry with it housing 115; such superimposed unit rides upon the ball 190 and employs such ball as a fulcruxn or pivot point when angularity to the adjacent conveyor is desired. Such lateral deflectio'n can be attained simultaneously with the raising or lowering of the preceding unit (or, as here shown, the superimposed unit) due to the construction heretofore described involved in making the conveyor frame slip-fitted, in a vertical plane, with the journalbox 230.-

- It is thus to be appreciated that adjustment in both lateral and ve1calplnes may be acc ornplished with great ease byreason of the peculiar construction of this' invention recited in the foregoihg; such adjustn aent in vertical and horizontal; a'ngularity may even be n 1ade while the -several unifs are being concurrently driven, one through the other, by a common power source.

Means have also beenprovided for engaging in locked relationship, and disengaging the adjacent ends ofcon veyor unitS in a quick and efiicient manner.- The details shown in Figure 9 should here be referred to. A rec tangularelement 270 is attached to the under side of plate 205. Atits.centfer isa depression or concavity 271 in the shape of a half hernisphere. As seen in Figures 4" and 5, this samqblock 270 also has a slot 273 extending fromone side approximzitely two-thirds through to the other side of the bottom' portion thereof. At the upper portion ofthe slot, two opposed grooves 275 are provided (see Figure S). This slot and thesegrooves are adapted to receivc a slicle member generally indicated a't 280. This has two tongueg 283 of a size perrnitting thern to easily slide back and fp'rth in the grooves 275 with out binding. The slide 280is actually U-shaped in formaav tion, cach of the sides 284 ofthe U being cu1'ved as at 286 to fit with some precision the contour of the ball 190. The U--shape, at the bottom portion of the U facing' the ball and adapted t o contact the latter, is also provicle'dl with a curved surface 285 approximating the spher ical shape of the ball 19.0.: It is thus seen that when the ball 190 is. fitted into the hemispherical depression of block 270 and the slide 280 -pre sjsed -against the lower surface of the ball (see Figures 4 and S), the latter is necessarily maintained in contacf with the spherical depression in block 270, being supportedand retained by the two sides 284 of the U-shaped member 280.

A relea xsing. mechanism for these several structure's is also provided. This take'stheform of the rod 300 which is screwed into or press, fitted' into the slide 280, extendg ing to the side of the unit through a block 306. This rod has a handle 305 for manual operation thereof. shown in Figuie 4 a Spring 312, p1essiflg agaihst a collar 310 monnted o1 r the rod, urges the latter into the locked position o; pcis itipn shown in the referred to figures. However, or'r rn'overnent of the rod to the left (viewing Figure 4 the spring is compresscd and the.slide 280 corisequ ently also movedto the left with a release of the ball 190.

1 The foregoing' structure presents a simplified means for Ijapidl Y interconneoting' or disassemblying several con- Veyor units. When connecting multiple units togcther, it isonly necessary tl1at stub shaft 173 be aligned with and fittccl into the square operiing in boss 260 of stub shaft 25 5. By po sitioning hall in the hernispherical soeket 2 71 .in block 270, the interlocking mechanism becomes aya ilable to retain the two ends of adjacent conveyor 1'1nits and the a ccompanying transmission equiprnent tog'ether in operative relationship. Conversely, in releasingthe interlocking mechanis rn, the ball readily slips from place when the slide 280 is withdrawn and the superim posed conveyor unit raised upwardly; it follows also tl1at the interconneeting shaft 173 is simil arly placed out of use l;iy tliis u}iwa rd rnovenrent.

Where a relatively large number of conveyor units are r'nployed, it may be desirable to use an additional booster power supply. Such a unit can be placed upon any one of the ii1tervening conveyors, preferably at the outby e ndthereof as shown in Figure 2. Referring to Figure 8 auch, a booster reeeives power frorn a motor M. The latter is generally geared down through a transmission G whichsupplie's torque to a sprocket 375, the latter delivering poWer through a chain,drive 371 -to shaft 86. As stated, a booster arrangernent of this natura -would find.nse on, for example, the third or fourth conveyor unit from the main Power supply located on the trammer. Also, it is quite apparerit that the power means could be either hydraulic 01" electric. In any event, the application ofa booster power supply, as herein shown, would not ir1terfere with the mobility,flexibility and interlocking character of the mechanism cornprising this invention.

v It is evident that many wariations are possible within the scope ofthis invention. However, it is not intended that the same be limited in anymanner except by the scope of the appefnded claims.

We clairn;

l.- In a flight.conveyor unit adapted to be readily connectedand disconnected in power transmitting relationship with adjacen like units, a forward chain and flight as sernbly supporting shaft and a rear chain and flight assernbly sup'porting shaft, means to drive said rear shaft whereby said forward. shaft is driven by said chain, said means includii1g a gear train on the forward end of said unit, one side of said gear train being interconnected to Sa'id forward shaft, the ot her side of said gear train haw ing a power take-oif shaft for interconnection with the rear shaft of an adjacent conveyor unit, a socket engag ing ball. centrally of said gear train, a gear assernbly in engagement with said rear drive shaft rotatable vertically with respect to said unit, and a ball engaging and disengaging interlock adjacent said rear drive shaft.

In a fl ight conveyor unit adapted to be readilyconnectedand disconnected in power tnansmitting relationship with adjacen like units, a forward chain and flight assembly supporting shaft and a rear chain and flight assembly suPporting shaft, means to drive said rear shaft whereby said forwz'1rd shaft is driven by said chain, said means including a gear train on the forward end of said unit, one side of said gear train being interconnected to said forward shaft, the other side of said gear train having a power take-otr' shaft for engagement with the rear shaft of an adjacent conveyor unit, said gear train being pivoted at the central portion thereof whereby said one side may be pivoted= with respect to the other side, a soc'ket engaging ball centrally of said gear train, a gear s'sembly in engagement with said rear drive shaft rotata-ble' vertically with. rt:'spect to saidunit, and a ball engaging and disengaging interlock means adjacent said rear drive shaft.

3. In a flight co11veyor unit adapted to be readily C0111- nected and disconnected in power transmitting relationship with adjacent, like unit s, a forward chain and flight assembly supporting shaft and a rear chain and flight assembly supporting shaft, means to drive said rear shaft whereby said forward shaft is driven by said chain, said means including a bifurcated gear train on the forward end of said unit, one side of said gear train being interconnected to said forward shaft, the other side of said gear train having a vertically disposed power take-ofi shaft, separate housings for each cf said sides, said housings and said sides being movable laterally in a horizontal plane with respect to each other, a socket engaging ball centrally of said gear train, a gear assembly in engagernent with said rear drive shaft rotatable vertically with respect to.said unit, a ball engaging and disengaging interlock means near said rear shaft for engagernent and disengagement with an adjacent conveyor unit, said interlock means including 'a ball receiving socket, rneans to maintain said ball in said socket comprising a slide means adapted to be rernovably positioned against a lower surface of said ball. '4. In a flight conveyor unit adapted to be readily counected and disconnected in power transmitting relationship with adjacent, like units, a forWard chain and flight assembly supporting shaft and a rear chain and flight assernbly supporting shaft, means to drive said rear shaft whereby said forward shaft is driven by said chain, said rneans including two interconnected housings on the forward end of said unit, said housings being interconnected and movable laterally with respect to each other, a gear train in said housings pivoted at the point of interconnection of said housings, one side of said gear train being interconnected to said forward shaft, the other side of said gear train having a vertically disposed power take-oif shaft, a socket engaging ball centrally of said gear train, a gear assembly in engagernent with said rear drive shaft rotatable vertically with respect to said unit, and a ball engaging and disengaging interlock means near said rear shaft for engagernent and disengagement with an adjacent conveyor unit 5. In a flight conveyor um't adapted to be readily cannected and disconnected in power transrnitting relationship with adjacent, like units, an elongated frame, a trough cn said frame, forward and real chain and flight supporting shafts journaled in said frame, means to drive said chain supporting shafts including a transmission, said transmission comprising an odd number of gears forming a gear train, the central gear of said gear train providing a pivot about which the gears on one side thereof may move angularly in a horizontal plane, the other side of said gear train being interconnected to said forward shaft, said one side of said gear train having a vertically disposed ower take-off shaft, said other side being movable laterally with respect to said one side, a socket engaging ball centnally of the gear train, a bevel gear assembly on said rear drive shaft, a gear box Containing a second bevel gear in emgagement with said first bevel gear, said gear box being rotatable vertically with respect to the frarne, said second bevel gear being in selective engagement with said take-off shaft and a ball engaging and disengaging interlock means ne.ar said rear shaft for engagement and disengagement with an adjacent conveyor unit, whereby said unit may be driven while disposed angularly with respect to the horizontal.

6. In a flight conveyor unit adapted to be readily counected and disconnected in power transmitting relationship with adjacent, like units, an elongated frame having a conveyor trough thereon, forward and rear chain supporting shafts on said fname, a drag chain and endless flight assembly mounted for conveyor motion on said shafts, a gear transmission at the forward end of said unit, said transmission comprising an odd number of meshed gears disposed in the same plane, the centnal of said gears providing a pivot for the gears on one side of said transrnission, means in association with said forward shaft to drive the transrnission including power takeoii means on said side of the transmission, a gear box containing a gear drive in interconznection with said rear shaft, said gear drive having power take-off interconnecting means, and maans permitting rotation of said gear box about the axis of said rear shaft whereby said unit may be driven by an adjacent unit while angularly disposed to the horizontal.

7. In a fli-ght conveyor unit adapted to be readily connected and disconnected in power transmitting relationship with adjacent, like units, an elongated frame having a conveyor trough thereon, forward and rear chain supporting shafts 011 said frame, a drag chain and endless flight assernbly mounted for conveyor motion on said shafts, a gear transrnission at the forward end of said unit, said transmission cornprising an odd number of meshed horizontally disposed gears, the central of said gaars providing a pivot for the gears on one side of said transmission, means in association with said forwatd shaft to drive the transmission including power takivoff means on said side of the transmission, a gear box containing a gear drive in interconnection with said rear shaft, said .gear drive having power take-off interconnection means, means for quick interconnection of said unit With said drive means including a socket engaging ball positioned above said central gear, |a ball engaging and disengaging interlock means near said rear drive shaft, and means permitting rotation of said gear box about the axis of said rear shaft vvhereby said unit may be driven by engagement With an adjacent unit while angularly disposed with respect to the horizontal.

8. In an endlass flight conveyor system, a series of units having forward and rear flight drive shafts, means to drive each of said rear shafts by interconnection thrrough an adjacent unit including a gear train on the forward end of each unit, one side of said gear train being interoonnected to said forward shaft, tl'l other side of said gear train having a vertically disposed ower takeoif shaft, a socket engaging ball centrally of said gear train, a gear assembly in engagement with said rear drive shaft rotatable vertically with respect to an adjacent unit,

' said gear assembly of one unit being in engagement with said power take-oif shaft of an adjacent unit, and an interlock for engagement and disengagernent with said ball of an .adjacent conveyor unit.

9. In an endless flight conveyor system, a series of nnits having forward and rear flight -drive -shafts means to drive each of said rear shafts by interconnection through an adjacent unit including a gear train on the forward end of each unit, said gear train belng bifurcated at the central portion thereof to forrn two housings movable angularly with respect to each other, one side of said gear train being interconnected to said forward shaft, the other side 0f said gear train having a vertically disposed ower take-ofl shaft, a socket engaging ball centrally cf said gear train, a gear assembly in engagernent With said rear drive shaft rotatable vertically With respect to an adjacent unit, said gear assembly being in engagement with said power take-oif shafit, and an interlock near said rear drive shaft for engagement and disengagernent with said ball of an adjacent conveyor unit.

10. In an en-dless flight conveyor, a series of units having forward and rear flight drive shafts, means to drive each of said rear shafts by interconnection through an adjacent unlt including a gear train on the forward end of each unit, one side of said gear train being interconnected to said forward shaft, the other side 0f said gear train having a vertically disposed power takte-01T shaft, said other side of said gear train being mounted in pivotal relationship With and in the same plane as said one side, a socket engaging ball centrally of said gear train, a gear assernbly in engagement with said rear drive shaft rotat- 

